Pompeius was a grammarian active in Africa, probably in the 5th c. CE, certainly later than Servius (early 5th c.) and before Isidore of Seville (d. 636). He wrote an extant commentary on the Ars of Aelius Donatus, with emphasis on the Ars maior (GL 5.95-312, with the missing beginning of the preface published by Holtz, RPh 45 (1971), 59-60); a new edition, badly needed, was announced by L. Holtz in 2005 but has not appeared), and possibly commentaries on Vergil and Terence. The commentary on Donatus, which takes pains to explain at length even the most elementary matters, was certainly written for use in the schools: phrases like ne puer erret occur repeatedly, and the reader whom Pompeius addresses as tu is imagined to be a teacher. His primary source was Servius, whom he does not name but whose unabridged commentary on Donatus he relied on heavily. The commentary is perhaps most striking because of its garrulous, discursive, and repetitive style: taken down by a notarius as Pompeius spoke (and he refers to himself speaking), it reflects the manner of a teacher at work. [R. Kaster]